Copyright to this resource is held by the creating agency and is provided here for educational purposes only. It may not be downloaded, reproduced or distributed in any format without written permission of the creating agency. Any attempt to circumvent the access controls placed on this file is a violation of United States and international copyright laws, and is subject to criminal prosecution.

Storm Water Monitoring Along
Loop 202 and Salt River
Final Report 602
Prepared by:
John Burton
Engineering and Environmental Consultants, Inc. (EEC)
7878 N. 16th Street, Suite 140
Phoenix, AZ85020
October 2010
Prepared for:
Arizona Department of Transportation
206 South 17th Avenue
Phoenix, AZ 85007
In cooperation with
U.S. Department of Transportation
Federal Highway Administration
The contents of this report reflect the views of the authors who are responsible for the facts and
the accuracy of the data presented herein. The contents do not necessarily reflect the official
views or policies of the Arizona Department of Transportation or the Federal Highway
Administration. This report does not constitute a standard, specification, or regulation. Trade or
manufacturers’ names which may appear herein are cited only because they are considered
essential to the objectives of the report. The U.S. Government and The State of Arizona do not
endorse products or manufacturers.
This report can also be found on our web site…
http://www.dot.state.az.us/ABOUT/atrc/Publications/Publications.htm
Technical Report Documentation Page
1. Report No.
FHWA-AZ-10-602
2. Government Accession No.
3. Recipient's Catalog No.
5. Report Date
October 2010
4. Title and Subtitle
Storm Water Monitoring Along Loop 202 and Salt River
6. Performing Organization Code
7. Author
John Burton
8. Performing Organization Report No.
10. Work Unit No.
9. Performing Organization Name and Address
Engineering and Environmental Consultants, Inc. (EEC)
7878 N. 16th Street, Suite 140
Phoenix, AZ85020
11. Contract or Grant No.
TRACS #999 SW 000
R0602 18P
On Call# 05-13
Task Order# JCV-077
13.Type of Report & Period Covered
FINAL REPORT
August 2006 – February
2009
12. Sponsoring Agency Name and Address
ARIZONA DEPARTMENT OF TRANSPORTATION
206 S. 17TH AVENUE
PHOENIX, AZ 85007
ADOT Project Manager: Estomih M Kombe, Ph.D., P.E.
14. Sponsoring Agency Code
15. Supplementary Notes
Prepared in cooperation with the U.S. Department of Transportation, Federal Highway
Administration
16. Abstract
A comprehensive research program for the characterization of storm water runoff from an Arizona
highway was conducted from January through December 2007. The study area covered a portion of
the Loop 202 freeway west of Mesa Drive to a retention basin east of Lindsay Road in Mesa, Arizona.
Storm water samples were collected from two storm water detention basins and a discharge point to
the Salt River. The study was conducted by manually collecting storm water samples with passive
automatic samplers and analyzing them for various roadway constituents. A primary objective of this
research effort was to establish baseline values of constituents in ADOT highway runoff, aiding in the
evaluation of related best management practices.
A total of 16 storm water samples was collected from the research area between January 2007 and
December 2007. The storm water sampling data indicates suspended solids (reported as total
suspended solids, or TSS) were present in 14 of the 16 samples collected and zinc (reported as total
zinc) was present in 13 out of 16 samples collected. Other heavy metals such as copper, lead, and
chromium were occasionally detected. Phosphorous and ammonia were detected only once during
this research program. TSS is the most significant pollutant, by mass, found in our nation’s
waterways, a standing consistent with the outcome of this research. It is important to note that
exceedance of an Environmental Protection Agency benchmark does not constitute a storm water
violation.
17. Key Words
18. Distribution Statement
Document is available to the
U.S. public through the
National Technical Information
Service, Springfield, Virginia
22161
19. Security Classification
Unclassified
20. Security Classification
Unclassified
21. No. of Pages
43
22. Price
23. Registrant's Seal
SI* (MODERN METRIC) CONVERSION FACTORS
APPROXIMATE CONVERSIONS TO SI UNITS APPROXIMATE CONVERSIONS FROM SI UNITS
Symbol When You Know Multiply By To Find Symbol Symbol When You Know Multiply By To Find Symbol
LENGTH LENGTH
in inches 25.4 millimeters mm mm millimeters 0.039 inches in
ft feet 0.305 meters m m meters 3.28 feet ft
yd yards 0.914 meters m m meters 1.09 yards yd
mi miles 1.61 kilometers km km kilometers 0.621 miles mi
AREA AREA
in2 square inches 645.2 square millimeters mm2 mm2 Square millimeters 0.0016 square inches in2
ft2 square feet 0.093 square meters m2 m2 Square meters 10.764 square feet ft2
yd2 square yards 0.836 square meters m2 m2 Square meters 1.195 square yards yd2
ac acres 0.405 hectares ha ha hectares 2.47 acres ac
mi2 square miles 2.59 square kilometers km2 km2 Square kilometers 0.386 square miles mi2
VOLUME VOLUME
fl oz fluid ounces 29.57 milliliters mL mL milliliters 0.034 fluid ounces fl oz
gal gallons 3.785 liters L L liters 0.264 gallons gal
ft3 cubic feet 0.028 cubic meters m3 m3 Cubic meters 35.315 cubic feet ft3
yd3 cubic yards 0.765 cubic meters m3 m3 Cubic meters 1.308 cubic yards yd3
NOTE: Volumes greater than 1000L shall be shown in m3.
MASS MASS
oz ounces 28.35 grams g g grams 0.035 ounces oz
lb pounds 0.454 kilograms kg kg kilograms 2.205 pounds lb
T short tons (2000lb) 0.907 megagrams
(or “metric ton”)
mg
(or “t”)
mg megagrams
(or “metric ton”)
1.102 short tons (2000lb) T
TEMPERATURE (exact) TEMPERATURE (exact)
ºF Fahrenheit
temperature
5(F-32)/9
or (F-32)/1.8
Celsius temperature ºC ºC Celsius temperature 1.8C + 32 Fahrenheit
temperature
ºF
ILLUMINATION ILLUMINATION
fc foot candles 10.76 lux lx lx lux 0.0929 foot-candles fc
fl foot-Lamberts 3.426 candela/m2 cd/m2 cd/m2 candela/m2 0.2919 foot-Lamberts fl
FORCE AND PRESSURE OR STRESS FORCE AND PRESSURE OR STRESS
lbf poundforce 4.45 newtons N N newtons 0.225 poundforce lbf
lbf/in2 poundforce per
square inch
6.89 kilopascals kPa kPa kilopascals 0.145 poundforce per
square inch
lbf/in2
SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380
TABLE OF CONTENTS
EXECUTIVE SUMMARY......................................................................................... 1
INTRODUCTION ......................................................................................................... 3
STORM WATER SAMPLING LOCATIONS...................................................... 5
SAMPLE LOCATION AT LINDSAY ROAD AND LOOP 202 ................................. 5
SAMPLE LOCATION AT GILBERT ROAD AND LOOP 202.................................. 5
SAMPLE LOCATION AT SALT RIVER AND LOOP 202 ........................................ 6
STORM WATER LITERATURE............................................................................. 7
STORM WATER RUNOFF FROM NORTH CAROLINA HIGHWAYS................... 7
STORM WATER RUNOFF FROM CALIFORNIA HIGHWAYS.............................. 7
TRACE ELEMENTS IN HIGHWAY AND URBAN RUNOFF.................................. 7
DATA COLLECTION PLAN.................................................................................... 9
SAMPLE COLLECTION METHOD............................................................................ 9
Storm Event Monitoring............................................................................................... 9
Sample Collection Protocol.......................................................................................... 9
Sample Preservation................................................................................................... 10
Sample Filtration ........................................................................................................ 10
Holding Times............................................................................................................ 10
Chain of Custody........................................................................................................ 10
LABORATORY SELECTION.................................................................................... 10
ANALYTICAL METHODS........................................................................................ 10
QUALITY ASSURANCE/QUALITY CONTROL..................................................... 12
Field Preparedness Procedures................................................................................... 12
Cleanliness ................................................................................................................. 12
Sample Collection ...................................................................................................... 12
Field Records.............................................................................................................. 12
Data Review and Validation ...................................................................................... 12
DATA MANAGEMENT............................................................................................. 13
Analytical Water Quality Data................................................................................... 13
Physical Observations ................................................................................................ 13
STORM WATER SAMPLING................................................................................ 14
STORM WATER SAMPLE COLLECTION DATES ................................................ 14
SAMPLE RESULTS FIRST QUARTER 2007 ........................................................... 15
Sampling Results January 11, 2007 ........................................................................... 15
Sampling Results February 6, 2007 ........................................................................... 16
Sampling Results February 22, 2007 ......................................................................... 17
Sampling Results March 30, 2007 ............................................................................. 18
SAMPLE RESULTS SECOND QUARTER 2007...................................................... 19
SAMPLE RESULTS THIRD QUARTER 2007.......................................................... 20
Sampling Results July 17, 2007 ................................................................................. 20
Sampling Results July 24, 2007 ................................................................................. 21
Sampling Results July 26, 2007 ................................................................................. 22
SAMPLE RESULTS FOURTH QUARTER 2007...................................................... 23
CONCLUSION AND RECOMMENDATIONS................................................. 25
BIBLIOGRAPHY........................................................................................................ 27
APPENDIX A: SITE MAPS.................................................................................... 29
APPENDIX B: SITE PHOTOS ............................................................................... 33
LIST OF TABLES
Table 1 - Analytical Methods ....................................................................... 11
Table 2 - Sample Location and Date Sampled ............................................. 14
Table 3 - Sample Results January 11, 2007.................................................. 15
Table 4 - Sample Results February 6, 2007.................................................. 16
Table 5 - Sample Results February 22, 2007................................................ 17
Table 6 - Sample Results March 30, 2007.................................................... 18
Table 7 - Sample Results May 15, 2007....................................................... 19
Table 8 - Sample Results July 17, 2007 ....................................................... 20
Table 9 - Sample Results July 24, 2007 ....................................................... 21
Table 10 - Sample Results July 26, 2007 ..................................................... 22
Table 11 - Sample Results December 4, 2007.............................................. 23
ABBREVIATIONS
ADHS Arizona Department of Health Services
ADOT Arizona Department of Transportation
ATRC Arizona Transportation Research Center
BMP best management practices
BOD biological oxygen demand
COD chemical oxygen demand
CWA Clean Water Act
EPA Environmental Protection Agency
ESC Environmental Science Corporation
NNS no numerical standard
NPDES National Pollutant Discharge Elimination System
QA/QC quality assurance/quality control
TDS total dissolved solids
TKN total Kjeldahl nitrogen
TPH total petroleum hydrocarbon
TSS total suspended solids
1
EXECUTIVE SUMMARY
A comprehensive research program for the characterization of storm water runoff from
the Loop 202 freeway in metropolitan Phoenix, Arizona, into two detention basins and
the Salt River was completed between January and December of 2007. The study was
conducted by manually collecting storm water samples utilizing passive automatic
samplers and analyzing them for various roadway constituents. A primary objective of
the storm water monitoring was to establish baseline values of constituents in freeway
runoff. The data will aid in evaluating the effectiveness of the Arizona Department of
Transportation’s (ADOT) best management practices (BMPs) for storm water
management along portions of the Loop 202.
Sixteen storm water samples were collected from the research area between January and
December 2007. The storm water sampling data indicate total suspended solids (TSS)
were in excess of the EPA benchmark in 14 of the 16 samples and the benchmark for zinc
was exceeded in 13 out of the 16 samples. Other heavy metals such as copper, lead, and
chromium were occasionally present. Phosphorous and ammonia were found only once
in this research program. Suspended solids (reported as total suspended solids, or TSS)
are the most significant pollutant, by mass, found in our nation’s waterways. The
outcome of this research with regard to the presence of TSS is thus consistent with
typical past findings. The high concentration of zinc (reported as total zinc) is likely the
result of wear and debris from automobile tires. Other heavy metal concentrations may
result from various automobile drippings, fumes, and particulates. It is worth noting that
in no instance did exceeding an EPA benchmark constitute a storm water violation.
2
3
INTRODUCTION
A comprehensive storm water sampling program was conducted along the Loop 202
freeway in metropolitan Phoenix, Arizona, that involved testing of effluent at the inlets to
two detention basins and an outlet into the Salt River, as more fully described in the next
chapter and the appendixes. The purpose of this monitoring program was to establish
baseline values of constituents in freeway runoff entering each detention basin and the
Salt River. The data allows ADOT to evaluate the effectiveness of the Best Management
Practices (BMPs) it has implemented along this portion of the Loop 202. The final
results of this program will be used to determine whether current BMPs are sufficient to
protect surface water quality or whether changes are necessary.
4
5
STORM WATER SAMPLING LOCATIONS
The sites for storm water sampling are described in this section. Figure 1 and Figure 2 in
Appendix A are maps showing the sampling location sites.
SAMPLE LOCATION AT LINDSAY ROAD AND LOOP 202
The Lindsay Road and Loop 202 sample location was near the northeast corner at the
inlet point of the ADOT detention basin south of the 202 and east of Lindsay (Appendix
B photos B-1 through B-3). This location was identified as Basin 1 for sampling
purposes and was selected for the following reasons:
• The detention basin is close to the Loop 202 and primarily receives storm water
runoff from the freeway.
• There are BMPs in use along the Loop 202 and this section of freeway is within
ADOT’s Municipal Separate Storm Sewer System (MS4) Phase I National
Pollutant Discharge Elimination System (NPDES) permitted area.
• There was safe access to the basin from surface streets and access from the
freeway was not required.
• The storm water samplers could be installed at the inlet point of this basin, which
is located at the northeast corner.
• An access gate is located near the inlet point, which provided additional security
for the samplers.
SAMPLE LOCATION AT GILBERT ROAD AND LOOP 202
The Gilbert Road and Loop 202 sample location is near the north side at the inlet point of
the ADOT detention basin (Appendix B photos B-4 and B-5). This location was
identified as Basin 2 for sampling purposes and was selected for the following reasons:
• The detention basin is close to the Loop 202 and primarily receives storm runoff
from the freeway.
• This detention basin is within a quarter-mile of the Lindsay Road detention basin
and would provide data for comparison between each basin.
• There are BMPs in use along the Loop 202 and this section of freeway is within
ADOT’s Phase I NPDES-permitted area.
• There was safe access to the basin from surface streets and access from the
freeway was not required.
• The storm water samplers could be installed at the inlet point of this basin, which
is located at the northeast corner.
• An access gate is located near the inlet point, which provided additional security
for the samplers.
6
SAMPLE LOCATION AT SALT RIVER AND LOOP 202
The Salt River and Loop 202 sampling location is located approximately 500 feet
northwest of ADOT’s pump station near Mesa Drive and the Salt River (Appendix B
photos B-6 through B-9). This location was identified as Salt River for sampling
purposes and was selected for the following reasons:
• It would provide ADOT with data concerning discharge into waters of the United
States.
• The two detention basins being sampled discharge to this location at the Salt
River.
• There was safe access to the basin from surface streets and access from the
freeway was not required.
• An access gate is located near the pump station, which provided additional
security for the samplers.
7
STORM WATER LITERATURE
A literature review was conducted that included literature from the Transportation
Research Information Services (TRIS) database at http://ntl.bts.gov/tris, and the Research
In Progress database located at http://rip.trb.org/search. No literature of direct relevance
was found for Arizona concerning storm water. However, several relevant studies
conducted outside Arizona concerning storm water in relation to highway and urban
runoff were identified. The studies discussed below were found to be relevant to this
research because they are associated with highway runoff or with vegetative slopes
adjacent to freeways.
STORM WATER RUNOFF FROM NORTH CAROLINA HIGHWAYS
Sampling and Testing of Stormwater Runoff from North Carolina Highways, conducted
for the North Carolina Department of Transportation (Wu and Allan 2001) — This
research pertains to a comprehensive monitoring program for characterization of North
Carolina highway runoff. Ten monitoring sites distributed in various regions were
included in the study. Contributing drainage areas ranged from 0.15 to 13.26 acres.
Roadway imperviousness ranged from 22% to 100% and traffic volumes ranged from
9,400 to 78,800 vehicles/day in both directions. Rainfall-runoff data and composite storm
water samples were obtained from 237 storm events. The effectiveness of vegetative
BMPs was assessed by comparing pollutant exports from three groups of paired
monitoring sites. A database was established for estimation of seasonal and annual
pollutant loads and event-mean concentrations. The study was part of the North Carolina
Department of Transportation's compliance with NPDES requirements.
STORM WATER RUNOFF FROM CALIFORNIA HIGHWAYS
Storm Water Monitoring & Data Management: Discharge Characterization Study
Report, conducted by the California Department of Transportation (2003) — This study
focuses on a water quality monitoring project designed to evaluate the removal of storm
water contaminants by existing vegetated slopes adjacent to freeways. The main objective
was to determine whether standard roadway design requirements resulted in buffer strips
that resulted in stormwater treatment equivalent to those buffer strips specifically
engineered for water quality improvement. The runoff through existing vegetated slopes
at four locations in northern and southern California was studied; variables such as
length, slope, vegetation density, and hydraulic loading were investigated in relation to
water quality. Concrete channels were constructed for capturing highway runoff after it
passed through existing buffer strips of varying widths at each location. The quantity and
quality of the runoff discharged from the buffer strips was compared to that observed at
the edge of the pavement. The performance of each vegetated shoulder was evaluated,
looking for changes in concentration of constituents typically found in highway runoff as
well as the load reduction caused by infiltration of storm water into these areas.
TRACE ELEMENTS IN HIGHWAY AND URBAN RUNOFF
A Synopsis of Technical Issues for Monitoring Trace Elements in Highway and Urban
Runoff, conducted by the U.S. Geological Survey (Breault and Granato 2000) — This
8
research project studied trace elements, described by the authors as “regulated for aquatic
life protection, are a primary concern in highway- and urban-runoff studies because
stormwater runoff may transport these constituents from the land surface to receiving
waters (p.1).” Concentrations in these waters may exceed natural ranges, with
unfavorable outcomes.
9
DATA COLLECTION PLAN
SAMPLE COLLECTION METHOD
Storm water samples were collected manually in accordance with ADOT’s Storm Water
Monitoring Guidance Manual for Municipal Separate Storm Sewer System (MS4)
Activities (ADOT 2005). Samples were collected from the first flush, which is within the
first 30 minutes of a storm event (storm event is described as at least 0.1 inch of rainfall
within 24 hours). To assist with first flush sampling, the research team used the
Nalgene® Stormwater Sampler. These samplers are placed at the sample collection point
prior to a storm event. Water flows through the collection funnel and into a sample
bottle. When the bottle is full, a floating ball valve seals off the sample collection port.
When the sample is retrieved, the collection funnel is removed and replaced with a leak-proof
cap and the sample is taken to the laboratory. This sample collection method
allows flexibility in collecting a first flush sample and for personnel safety during sample
acquisition. Additionally, the sample bottles were inspected bi-weekly once they had
been placed in the appropriate locations. This was to ensure they were not contaminated
or tampered with during the wet periods.
Storm Event Monitoring
Storm events were monitored by reviewing data on the Flood Control District of
Maricopa County rainfall information Web site. This Web site is located at
http://156.42.96.39/xrainmaps.html and provides real time data. Sampling personnel
traveled to the research area when storm water sensors indicated that a qualifying storm
event had occurred. If storm events occurred during the evening, sampling personnel
traveled to the research area the next morning to retrieve the sample bottles.
Sample Collection Protocol
This storm water sampling study employed clean sampling techniques to minimize
potential sources of sampling contamination. Sampling personnel adhered to the
following rules while collecting water samples:
• Do not eat, drink, or smoke during sample collection.
• Never sample near a running vehicle.
• Do not park vehicles in the immediate sample collection area.
• Always wear clean, powder-free, nitrile gloves when handling sample containers and
lids.
• Never touch the inside surface of a sample container or lid, even with gloved hands.
• Never allow the inner surface of a sample container lid to be in contact with any
material other than the sample water.
• If manual sample collection is done, do not overfill sample containers as preservative
may be lost.
• Do not allow any object or material (including rain drops) to fall into or make contact
with the collected water sample.
• Replace and tighten sample container lids immediately after sample collection.
10
Sample Preservation
To prolong the stability of the collected samples during transport and storage, chemical
preservatives are added to the sample bottles for certain analyses (Table 1). The
laboratory provided sample bottles with appropriate preservatives for each analysis
requested. All samples were placed on ice immediately after collection.
Sample Filtration
Sample filtration is required when collecting samples for dissolved metals analysis.
Filtration for metals was done by the analytical laboratory to reduce the potential for
contamination in the field, especially during storm conditions.
Holding Times
The holding time starts when sample collection is complete and is counted until
extraction, preparation, and analysis of the sample at the laboratory are complete. In this
and similar research projects, specified maximum acceptable holding times for each
analytical method are closely watched.
Chain of Custody
The laboratory provided chain-of-custody (COC) forms. They were completed by
monitoring personnel for samples submitted to the analytical laboratory. The purpose of
COC forms is to keep a record of the sample submittal information and to document the
transfer of sample custody. Sample date, sample location, and analyses requested were
noted on the COC form. Any special instructions for the laboratory were also noted on
the COC form, such as specifications of quality control requirements (e.g., duplicate
samples). The COC form was signed by both the person relinquishing the samples and
the person receiving the samples every time the samples changed hands, thus
documenting the chain of custody. No third party was used to collect, prepare, or deliver
samples.
LABORATORY SELECTION
Environmental Science Corporation (ESC) of Mt. Juliet, Tennessee, performs laboratory
analysis of the samples. ESC’s laboratory, which has been certified by the Arizona
Department of Health Services (ADHS #AZ0612), did the analyses of the storm water
samples for this project.
ANALYTICAL METHODS
Storm water samples were collected and analyzed in accordance with ADOT’s Storm
Water Monitoring Guidance Manual for MS4 Activities (ADOT 2005).
11
Table 1 - Analytical Methods
Parameter Method No. Holding Time Preservation Reporting
Limit
BOD5 EPA 405.1/SM
5210B
48 hours 4°C 3 mg/L
COD EPA 410.1/SM
5220D
28 days 4°C and H2SO4 to pH<2 10 mg/L
Hardness EPA 200.7/SM
2340B
6 months HNO3 to pH<2 2 mg/L
pH EPA 150.1 Analyze
immediately
None 0.1 std. units
Water
Temperature
EPA 170.1/SM
2550B
Analyze
immediately
None 0.1 C
Specific
Conductance
EPA 120.1/SM
2510B
28 days 4°C 2 μmhos/cm
TDS EPA 160.1/SM
2540C
7 days 4°C 1 mg/L
TSS EPA 160.2 7 days 4°C 1 mg/L
Turbidity EPA 180.1/SM
2130B
48 hours 4°C 0.1 NTU
Color EPA 110.2/SM
2120
48 hours 4°C 1 units
NO3-N EPA 300.0/SM
4500
48 hours 4°C 10 mg/L
NO2-N EPA 300.0/SM
4500
48 hours 4°C 0.1 mg/L
Total
Phosphorous
EPA 365.1/SM
4500
28 days 4°C and H2SO4 to pH<2 0.03 mg/L
TKN EPA 351.4 28 days 4°C and H2SO4 to pH<2 0.1 mg/L
Ammonia EPA 350.1/EPA
350.3
28 days 4°C and H2SO4 to pH<2 0.03 mg/L
Cadmium 5 μg/L
Chromium 10 μg/L
Copper 10 μg/L
Lead 30 μg/L
Zinc
EPA 200.8 [a]
Filter for dissolved
fraction and
preserve within 48
hours;
Holding time is 6
months to
analysis
Filter dissolved samples
before preservation;
4°C and HNO3 to pH<2
10 μg/L
TPH EPA 418.1W 14 days 4°C and 1:1 H2SO4 1 mg/L
Total Phenols EPA 420.1 28 days 4°C and H2SO4 to pH<2 0.1 mg/L
DDE EPA 608 7 days to
extraction; 40
days to analysis
4°C and Na2S2O3 if
chlorinated to pH 5-9
0.01 μg/L
Surfactants
(detergents)
EPA/425.1/SM
5540
48 hours 4°C 0.02 mg/L
12
QUALITY ASSURANCE/QUALITY CONTROL
The quality assurance/quality control (QA/QC) program ensured that samples collected
were of the highest quality and that the laboratory analyzing the samples produced
reliable results. The QA/QC procedures implemented for this research project are further
described in this section.
Field Preparedness Procedures
Field QA/QC procedures included preparations before sampling events occurred.
Sampling equipment, sample bottles, and forms were readied for each monitoring site
prior to a monitoring event to ensure that the necessary equipment was ready and
available. By preparing for an event ahead of time, the possibility of filling incorrect
bottles or mislabeled bottles was avoided. All equipment was readied for the next
monitoring event upon return from the previous monitoring event.
Cleanliness
Cleanliness of the sampling equipment is vital to ensuring that contamination is not
introduced from a controllable factor. Sample bottles were certified clean by the
laboratory to minimize sample contamination. Cleanliness techniques were used when
collecting as well as handling the samples.
Sample Collection
The same technician collected the samples at all three locations. This improved data
quality by maintaining the same collection procedures for all sampling locations.
Field Records
General information relating to each sampling event was recorded at the monitoring site.
This includes such information as sample collection date and time. Other recorded
information is listed under ‘Physical Observations.’ General information included:
• Date
• Time
• Sample technician’s name
• Site name
• A general description of site conditions
Data Review and Validation
The data for each sampling event was reviewed and validated. All reports from the
contract laboratory were reviewed upon receipt. A review was made of the holding
times, proper chain-of-custody procedures, preservation, etc. A data validation sheet was
completed for each data set.
13
DATA MANAGEMENT
Sampling data were organized and each monitoring site’s data clearly labeled. Two
primary types of data were collected for this research program: (1) analytical water
quality data and (2) physical observations.
Analytical Water Quality Data
The analytical water quality data is a direct result of the field measurements taken and the
samples collected during a monitoring event. The samples were analyzed for the
pollutants listed in Table 1. Data was reported from the contract laboratory in hard copy
and an electronic file. Reported measurements included:
• pH
• Air temperature
• Water temperature
• Conductivity
Physical Observations
Physical observations were recorded and retained to supplement the analytical water
quality data. Photographs were taken and a site sketch was made. Also recorded in this
category were observations such as:
• Estimated discharge
• Vegetative growth
• Oily sheen
• Surface scum
• Deposits
• Odor
• Land use type
14
STORM WATER SAMPLING
Storm water samples collected and analyzed as part of this research project have been
compared to an Environmental Protection Agency (EPA) benchmark level if one was
available (not all parameters analyzed have benchmark levels). It is important to note
that exceeding a benchmark does not constitute a storm water violation. This section
provides a summary of sampling results for the samples collected throughout 2007.
STORM WATER SAMPLE COLLECTION DATES
Sixteen storm water samples were collected from the research areas between January
2007 and December 2007. Due to the differences in rainfall and storm water drainage
patterns, each sampling location did not have an equal amount of storm water flow.
Therefore, sample collection was not evenly distributed at each location. Table 2
identifies the sample location and the date samples were collected:
Table 2 - Sample Location and Date Sampled
Date Sampled Sample Location
Basin 1 Basin 2 Salt River Site
01-11-07 X X
02-6-07 X X
02-22-07 X X
03-30-07 X X X
05-15-07 X X
07-17-07 X
07-24-07 X
07-26-07 X X
12-04-07 X
X – Indicates sample collected at this location and date
The difference between the number of samples collected at Basin 1 and the other sites is
due to low storm water flow during storm events. This may be the result of storm water
runoff from the Loop 202 flowing through a dirt-lined ditch prior to discharging to Basin
1. It is likely that in many instances storm water soaked into the ground along this path,
not reaching Basin 1. The other two sample locations each have concrete-lined channels
that directed storm water to the sample locations.
15
SAMPLE RESULTS FIRST QUARTER 2007
Storm water samples were collected on the following dates: January 11, 2007, February
6, 2007, February 22, 2007, and March 30, 2007. Each sampling event for this first
quarter of 2007 is further discussed in this section.
Sampling Results January 11, 2007
Storm water samples were collected on January 11, 2007, from Basin 2 and the Salt River
site (Table 3). Storm water flow at Basin 1 was not of an adequate amount to fill the
sample bottles and so no analyses were completed. The volumes of storm water collected
from Basin 2 and the Salt River site were not enough to perform dissolved metal
analyses. The analytical results that are in boldface indicate the sample collected from
the Salt River exceeded the EPA benchmarks for total suspended solids (TSS), total
copper, and total zinc.
Table 3 - Sample Results January 11, 2007
Sampling Location and Result (mg/L)
Constituent Basin 1 Basin 2 Salt River
Benchmark
mg/L
Total Dissolved Solids -- 760 300 NNS
Total Suspended Solids -- 19 1100 100
Turbidity -- 29 36 NNS
Specific Conductance -- 1,200 umos/cm 480 umos/cm NNS
Hardness -- 350 380 NNS
BOD -- <5 8.3 30
COD -- 32 96 120
Color -- 62 pcu 68 pcu NNS
pH -- 7.46 su 6.95 su 6.0 – 9.0
Conventional
Temperature -- 56.9 °F 57.1 °F NNS
Nitrite -- <0.10 <0.10 NNS
Nitrate -- 1.4 0.77 NNS
Ammonia Nitrogen -- 0.35 <0.10 19.00
Total Phosphorus -- 0.11 2.0 2.0
Nutrients
Total Kjeldahl Nitrogen -- 3.3 3.6 NNS
Cadmium (Cd) -- <0.005 0.010 0.0159
Chromium (Cr) -- <0.01 0.050 NNS
Copper (Cu) -- <0.02 0.094 0.0636
Lead (Pb) -- <0.005 0.056 0.0816
Metals,
Total
Zinc (Zn) -- <0.03 0.38 0.117
Dissolved Cadmium (Cd) -- -- -- NNS
Dissolved Chromium (Cr) -- -- -- NNS
Dissolved Copper (Cu) -- -- -- NNS
Dissolved Lead (Pb) -- -- -- NNS
Metals,
Dissolved
Dissolved Zinc (Zn) -- -- -- NNS
4,4 – DDE (pesticide) --